I'm an Australian citizen, but have been living in Japan for 5 years thus even paying taxes and insurances etc here. (so im pretty sure my Medicare card isnt valid anymore in Aus as i dont pay taxes there anymore) I'm only on a working visa in Japan though so am not considered as a 'permanent resident' by legal wording. However, obviously my living address is in Japan and I'm allowed to leave and return to Japan during the length of my visa. I know others have asked this same type of question but I'm still a little unsure about it. I'll be traveling back to Australia very soon.
He way to think about residency as it relates to the policy is to ask where you'd want us to repatriate you to in the event of a medical emergency.
Be aware that our cover ends once we get you home, so I'd suggest you put Australia as if it was something truly serious, Medicare then picks up the bills once you are home, whereas if we get you back to Japan I'm pretty sure their public system won't.
Hope this helps.
Simon almost 6 years ago